TWI748527B - Charged particle beam device - Google Patents

Abstract

The present invention provides a charged particle beam device capable of reducing the positional deviation between the secondary beams generated in a beam splitter. To this end, it is characterized by having a charged particle beam source which irradiates a plurality of primary beams On the sample; a plurality of detectors, which detect each of the secondary beams emitted from the sample corresponding to each of the primary beams; and a beam splitter, which directs the secondary beams And the charged particle beam device is further provided with a deflector arranged between the beam splitter and the detector to correct the secondary beam generated in the beam splitter The position offset between the beams.

Description

Charged particle beam device

The present invention relates to a charged particle beam device, in particular to a technology that uses a plurality of charged particle beams to increase productivity.

The charged particle beam device is a device that detects secondary charged particles such as secondary electrons or reflected electrons released from the sample by irradiating charged particle beams such as electron beams or ion beams to the sample, and generates Observe the image of the fine structure of the sample, and the charged particle beam device is used in semiconductor manufacturing steps, etc. In the semiconductor manufacturing process, it is required to increase the production capacity, and sometimes a charged particle beam device of the multi-beam method is used. The charged particle beam device of the multi-beam method irradiates a plurality of charged particle beams to the sample and detects Device to detect the secondary charged particles released from the sample.

The charged particle beam device of the multi-beam method is equipped with a beam splitter. The beam splitter is designed to combine the primary beam as the charged particle beam irradiated to the sample and the secondary charged particles released from the sample. The secondary beam is separated, and the secondary beam is deflected in a direction different from the primary beam. However, in the beam splitter, the secondary beam will produce deflection chromatic aberration.

Patent Document 1 discloses that an electron beam device of a multi-beam system is provided with an electrostatic deflector for correcting chromatic aberrations generated by an electromagnetic deflector as a beam splitter.

Prior art literature Patent literature

Patent Document 1: International Publication No. 2006/101116

However, Patent Document 1 does not consider the positional shift between the secondary beams generated in the beam splitter. Regarding the secondary beam, the length of the interval affected by the electric or magnetic field formed by the beam splitter differs depending on the position of the incident beam splitter, and the longer the interval of action in the electric or magnetic field, the deflection vector Bigger. That is, due to the difference in the position of the incident beam splitter, there will be a position shift between the secondary beams. If the position shift is too large, the detection of the secondary beam will be hindered.

Therefore, the object of the present invention is to provide a charged particle beam device capable of reducing the positional deviation between the secondary beams generated in the beam splitter.

In order to achieve the above-mentioned object, the present invention is characterized in that it is a charged particle beam device, comprising: a charged particle beam source which irradiates a plurality of primary beams to a sample; and a plurality of detectors whose detection corresponds to the above-mentioned primary beam Each of the beams and each secondary beam emitted from the above-mentioned sample; and a beam splitter that deflects the above-mentioned secondary beam in a direction different from the above-mentioned primary beam; and the charged particle beam device Furthermore, a deflector is provided, which is provided between the beam splitter and the detector, and corrects the positional deviation between the secondary beams generated in the beam splitter.

According to the present invention, it is possible to provide a charged particle beam device capable of reducing the positional deviation between the secondary beams generated in the beam splitter.

101: Electron source

102: electron beam

103: Multi-beam forming part

104: One beam

104a: one beam

104b: one beam

104c: one beam

105: beam splitter

105a: positive electrode

105b: negative electrode

105c: positive pole

105d: negative pole

106: Specimen

107: Secondary beam

107a: secondary beam

107b: Secondary beam

107c: secondary beam

108: Detector

110: deflector

120: Control Department

201: Power of Electric Field E

202: Power of Magnetic Field B

301: Action Range

301a: range of action

301c: range of action

302: Plane

701: Intersection

901: Sample for adjustment

1001: Adjustment screen

1002: Ratio input part

1003: Shooting start button

1004: SEM image display

1005: Resolution display unit

1006: Confirm button

1401~1405: Multiple electrodes or magnetic poles

B: Magnetic field

E: Electric field

FIG. 1 is a schematic diagram showing an example of the charged particle beam device of the first embodiment.

2(a) and (b) are diagrams illustrating the beam splitter 105 using ExB.

3 is a diagram illustrating the secondary beam 107 in the electric field E or the magnetic field B formed by the optical splitter 105.

FIG. 4 is a diagram showing an example of the position shift between the secondary beams 107 in the plane 302.

5(a) and (b) are diagrams illustrating the correction of the position shift between the secondary beams 107 by the deflector 110. FIG.

6 is a diagram illustrating the deflection angle of the secondary beam 107 formed by the beam splitter 105 and the deflector 110.

FIG. 7 is a diagram illustrating the correction of the beam shape of the secondary beam 107 by the deflector 110.

FIG. 8 is a diagram showing an example of the processing flow of adjusting the ratio of the electric field and the magnetic field of the deflector 110 using ExB.

FIG. 9 is a diagram showing an example of an adjustment sample 901 used for adjustment of the ratio of the electric field to the magnetic field of the deflector 110 using ExB.

FIG. 10 is a diagram showing an example of an adjustment screen 1001 for adjusting the ratio of the electric field and the magnetic field of the deflector 110 using ExB.

FIG. 11 is a schematic diagram showing a modified example of the charged particle beam device of the first embodiment.

FIG. 12 is a schematic diagram showing an example of the charged particle beam device of the second embodiment.

FIG. 13 is a schematic diagram showing an example of the charged particle beam device of the third embodiment.

FIG. 14 is a schematic diagram showing an example of the deflector 110 of the third embodiment.

Hereinafter, according to the attached drawings, the embodiment of the charged particle beam device of the present invention Be explained. The charged particle beam device is a device for observing the sample by irradiating a charged particle beam represented by an electron beam to the sample, and there are various devices such as a scanning electron microscope or a scanning transmission electron microscope. Hereinafter, as an example of a charged particle beam device, a scanning electron microscope of a multi-beam method that uses a plurality of electron beams to observe a sample will be described.

Example 1

Using FIG. 1, the overall structure of the scanning electron microscope of this embodiment will be described. The scanning electron microscope is equipped with: an electron source 101 (an implementation of the "charged particle beam source" in the request), a multi-beam forming unit 103, a beam splitter 105, a detector 108, a deflector 110, and a control unit 120 .

The electron source 101 is a device that generates an electron beam 102 by releasing electrons and accelerating them. The electron beam 102 generated by the electron source 101 is separated into a plurality of primary beams 104 by the multi-beam forming part 103. Fig. 1 illustrates the primary beams 104a, 104b, and 104c separated into three. The primary beams 104a, 104b, and 104c are incident on the beam splitter 105, travel toward the sample 106, and are irradiated. Furthermore, the primary beams 104a, 104b, and 104c irradiated to the sample 106 are focused and deflected by a focusing lens, an objective lens, and a scanning deflector (not shown).

From the sample 106 irradiated with the primary beams 104a, 104b, 104c, secondary electrons, reflected electrons, etc. are released as secondary beams 107a, 107b, 107c. The secondary beams 107a, 107b, and 107c are emitted corresponding to each of the primary beams 104a, 104b, and 104c, and enter the beam splitter 105 to be deflected.

Using FIG. 2, an example of the beam splitter 105 will be described. 2 is a view of the beam splitter 105 viewed from the electron source 101 side. FIG. 2(a) shows the effect on the primary beam 104, and FIG. 2(b) shows the effect on the secondary beam 107. The beam splitter 105 has a positive electrode 105a, a negative electrode 105b, a positive magnetic pole 105c, and a negative magnetic pole 105d, and forms an electric field E from the positive electrode 105a to the negative electrode 105b (an implementation type of the "first electric field" in the claim State) and from the positive magnetic pole 105c direction The magnetic field B of the negative magnetic pole 105d (an implementation type of the "first magnetic field" in the request). That is, the electric field E and the magnetic field B orthogonal to each other are formed in a plane orthogonal to the primary beam 104. Because the electric field E is orthogonal to the magnetic field B, it is called ExB. Furthermore, if the electric field E and the magnetic field B are orthogonal, the number of electrodes and magnetic poles is not limited to two poles, and can also be eight poles or twelve poles.

As shown in FIG. 2(a), the force 201 of the electric field E and the force 202 of the magnetic field B act on the primary beam 104 in opposite directions. When the force 201 and the force 202 are equal in magnitude, the primary beam 104 travels straight. On the other hand, as shown in Figure 2(b), the force 201 of the electric field E and the force 202 of the magnetic field B act on the secondary beam 107 in the same direction, so the secondary beam 107 is driven by the combined force of the force 201 and the force 202 It is deflected in a direction different from that of the primary beam 104. That is, the primary beam 104 and the secondary beam 107 are separated due to the action of the electric field E and the magnetic field B formed by the beam splitter 105.

Return to the description of Figure 1. The secondary beams 107a, 107b, and 107c deflected in a direction different from the primary beams 104a, 104b, and 104c enter the detector 108 via the deflector 110 described below. The detector 108 is a device having a plurality of detection units for detecting each of the secondary beams 107a, 107b, and 107c. The detection signal of the detector 108 is sent to the control unit 120 for generating an observation image of the sample 106.

The control unit 120 is a device that controls each part of the scanning electron microscope, and is composed of, for example, a general-purpose computer. A computer is equipped with a processor such as a CPU (Central Processing Unit), a memory device such as a memory or HDD (Hard Disk Drive), an input device such as a keyboard or a mouse, and a display device such as a liquid crystal display. The control unit 120 executes various processes by expanding the programs stored in the HDD in the memory so that the CPU executes the programs. Furthermore, a part of the control unit 120 may be constituted by hardware such as a dedicated circuit board. The control unit 120 generates and displays an observation image based on the detection signal sent from the detector 108.

In order to generate a suitable observation image, it is preferable to detect the secondary beam 107 emitted from the sample 106 by the detector 108 without any omission. However, due to the beam splitter 105 The positional deviation between the secondary beams 107 generated in, may hinder the detection of the secondary beam 107 by the detector 108. Hereinafter, the position shift between the secondary beams 107 will be described.

Using FIG. 3, the secondary beam 107 in the electric field E or the magnetic field B formed by the beam splitter 105 will be described. The electric field E or the magnetic field B formed by the beam splitter 105 is diffused in the traveling direction of the secondary beam 107. Therefore, regarding the secondary beam 107, the length of the interval affected by the electric field E or the magnetic field B depends on the incident beam The position of the separator 105 is different. For example, the action interval 301a of the outer secondary beam 107a of the deflected secondary beam 107 is longer than the action interval 301c of the inner secondary beam 107c. As a result, the outer secondary beam 107a is deflected more greatly than the inner secondary beam 107c.

Using FIG. 4, the position shift between the secondary beams 107 in the plane 302 of FIG. 3 will be described. Furthermore, in order to simplify the description, the image plane of the sample that is substantially orthogonal to the deflected secondary beams 107 and each secondary beam 107 is focused to the greatest extent is selected as the plane 302. In addition, 9 secondary beams 107 are illustrated in FIG. 4. Since the amount of deflection of each secondary beam 107 differs depending on the length of the action area 301 of the electric field E or the magnetic field B, the incident position of the beam splitter 105 is different, and the secondary beam 107 that reaches the plane 302 is different. There is a position shift between them. That is, since the outer secondary beam 107a is more deflected than the inner secondary beam 107c, the beam interval is enlarged. If the positional deviation between the secondary beams 107 is too large, the secondary beam 107 that cannot be incident on the detector 108 will be generated, thereby hindering the detection of the secondary beam 107.

In addition, the secondary beam 107 has energy dispersion, and the amount of deflection varies depending on the energy, so the beam shape is deformed. That is, the secondary beam 107 with a larger energy is less deflected by the electric field E or the magnetic field B than the secondary beam 107 with a smaller energy. Therefore, the beam shape of the secondary beam 107 is shown in the figure 4 shows the deformation. The distortion of the beam shape will reduce the detection resolution of each secondary beam 107.

Therefore, in this embodiment, the positional deviation between the secondary beams 107 generated in the beam splitter 105 is corrected by the deflector 110 provided between the beam splitter 105 and the detector 108. The deflector 110 is a device that deflects the secondary beam 107 in a direction opposite to the beam splitter 105, such as an electric field sector including a positive electrode and a negative electrode or a magnetic field sector including a positive magnetic pole and a negative magnetic pole. In order to deflect the secondary beam 107 by the deflector 110 as shown in Fig. 1, an electric field sector with a positive electrode on the right side and a negative electrode on the left side or a magnetic field with a positive pole on the front and a negative pole on the back are used. Sector. In addition, ExB which forms an electric field and a magnetic field orthogonal to each other can also be used for the deflector 110.

Using FIG. 5, the correction of the position shift between the secondary beams 107 by the deflector will be described. FIG. 5(a) shows the effect of the deflection of the deflector 110, and FIG. 5(b) shows the configuration when the secondary beam 107 corrected by the deflector 110 is incident on the detector 108. The deflector 110 deflects the secondary beam 107 in the direction opposite to the beam splitter 105, so the position shift in the direction opposite to that of FIG. 4 is generated in the secondary beam 107. As a result, the position shifts generated by the beam splitter 105 and the deflector 110 respectively cancel each other out. As shown in FIG. 5(b), the secondary beam 107 with a reduced position shift can be incident on the detector 108. In addition, regarding the deformation of the beam shape accompanying the energy dispersion of the secondary beam 107, the effects of the beam splitter 105 and the deflector 110 cancel each other out, so that the beam shape can be improved.

Using FIG. 6, the deflection angle of the secondary beam 107 formed by the beam splitter 105 and the deflector 110 will be described. When the angle at which the secondary beam 107b at the center of the plurality of secondary beams 107 is deflected by the beam splitter 105 is set to θ1, the angle at which the secondary beam 107b is deflected by the deflector 110 is set as For θ2, θ1 and θ2 are in opposite directions. In addition, the incident angle of the secondary beam 107b to the detector 108 is preferably a right angle. Therefore, when the tilt angle of the detector 108 with respect to the beam splitter 105 is set to θ, the deflection angle θ2 of the deflector 110 preferably satisfies the following equation.

θ2=θ-θ1...(Equation 1)

Using FIG. 7, the correction of the beam shape of the secondary beam 107 by the deflector will be described. Fig. 7 shows the orbits of the secondary beams 107b having different energies, that is, the secondary beams 107b-L, 107b-M, and 107b-H. Furthermore, the secondary beam 107b-L has low energy, the secondary beam 107b-M has medium energy, and the secondary beam 107b-H has high energy.

The deflection angle formed by the deflector 110 depends on the energy of the secondary beam 107b, and the higher the energy, the smaller. Therefore, the deflector 110 deflects the secondary beam 107 in the direction opposite to the beam splitter 105, thereby improving the deformation of the beam shape, especially in the secondary beams 107b-L, 107b-M, 107b- At intersection 701 of H, the distortion of the beam shape disappears.

When the deflector 110 is an electric field sector or a magnetic field sector, the size of the electric field or magnetic field of the deflector 110 is determined according to the deflection angle θ2, so the position of the intersection 701, which is the point where the deformation of the beam shape disappears, is also determined Uniquely determined. The secondary beam 107 after the deformation of the detection beam shape disappears can become the highest detection resolution, so it is best to install the detector 108 at the position of the intersection 701. However, when the detection resolution is set to a specific value or more, it is only necessary to install a detector at a position where the size of the beam shape of the detected secondary beam 107 is below the specific value, that is, near the intersection 701 108 is fine.

Moreover, when the deflector 110 is ExB, the deflection angle θ2 formed by the deflector 110 is the deflection formed by the electric field E2 of ExB (an implementation type of the "second electric field" in the request) The angle θ2 (E2) and the deflection angle θ2 (B2) formed by the magnetic field B2 (an implementation of the "second magnetic field" in the request) are expressed by the following formula.

θ2=θ2(E2)+θ2(B2)...(Equation 2)

The combination of the electric field E2 and the magnetic field B2 whose θ2 is a specific value continuously exists. On the other hand, if the ratio of the electric field E2 to the magnetic field B2 changes, the position of the intersection 701 will also move. That is, by adjusting the ratio of the electric field E2 and the magnetic field B2, the position of the intersection 701 can be moved, and the control setting is The detection resolution of the detector 108 at a specific position.

Using FIG. 8, an example of the processing flow of adjusting the ratio of the electric field E2 and the magnetic field B2 of the deflector 110 using ExB will be described.

(S801)

The adjustment sample 901 as illustrated in FIG. 9 is placed in the observation field of the scanning electron microscope. The ratio of the electric field E2 to the magnetic field B2 is adjusted based on the difference of the images obtained by each beam. Therefore, the adjustment sample 901 is used as a sample having a different shape at each position where a plurality of primary beams 104 are irradiated. FIG. 9 illustrates an adjustment sample 901 irradiated with 9 primary beams 104, and each of the 9 positions has a different shape. If a plurality of secondary beams 107 emitted from different positions of the adjustment sample 901 are incident on the same detection part of the detector 108, they will become SEM images with different shapes. That is, based on the evaluation of the SEM image of the adjustment sample 901, the degree of separation D of the secondary beam 107 can be calculated, for example, by using the following formula.

D=Si(i)/Si...(Equation 3)

Here, i is the number of a plurality of beams, Si is the sum of the signal of the i-th SEM image in the SEM images of each beam, and Si(i) is the signal of the i-th beam contained in Si quantity. According to (Equation 3), if the SEM image of each beam is only the signal amount of the beam, then D=1, and if the signal amount of the beam is not included, then D=0.

Furthermore, a sample of the same shape used for irradiating a plurality of primary beams 104 can be arranged instead of the adjustment sample 901, and the degree of separation D can be calculated based on the deviation of the shape in the SEM image of each beam.

(S802)

Using the adjustment screen 1001 illustrated in FIG. 10, the operator adjusts the ratio of the electric field E2 and the magnetic field B2 of the deflector 110. The adjustment screen 1001 has a ratio input unit 1002, and the shooting start button Button 1003, SEM image display unit 1004, resolution display unit 1005, and confirmation button 1006. The ratio input unit 1002 is used to adjust the ratio of the electric field E2 and the magnetic field B2 of the deflector 110. That is, the operator inputs the ratio of the electric field E2 and the magnetic field B2 to the ratio input unit 1002. Furthermore, when the deflection angle θ2 formed by the deflector 110 is determined, the value of the other can be calculated from the value of one of the electric field E2 and the magnetic field B2 by (Equation 2), so that only the electric field E2 and The value of one of the magnetic field B2.

(S803)

When the operator clicks the shooting start button 1003, the SEM image of the adjustment sample 901 is captured, and the control unit 120 evaluates the SEM image to calculate the degree of separation of the secondary beam 107. For the calculation of the degree of separation, for example, (Equation 3) is used. The taken SEM image is displayed on the SEM image display part 1004, and the calculated resolution is displayed on the resolution display part 1005. Furthermore, in this step, the lens or the alignment machine can be adjusted.

(S804)

It is determined whether the degree of separation calculated in S803 is within the allowable range. When the operator makes a judgment, if the degree of separation is within the allowable range, click the confirmation button to end the processing flow of FIG. 8, and if it is not within the allowable range, return to S802 to readjust the ratio.

Through the above processing flow, the ratio of the electric field E2 and the magnetic field B2 of the deflector 110 can be adjusted in such a way that the separation degree of the secondary beam 107 becomes the allowable range, and the detection resolution can be improved. Furthermore, while changing the ratio of the electric field E2 and the magnetic field B2 by the control unit 120, the imaging and resolution of the SEM image can be repeatedly calculated, and the ratio can be adjusted so that the resolution becomes a predetermined allowable range.

Furthermore, when the voltage and current supplied to the deflector 110 in order to form the electric field E2 and the magnetic field B2 are V2 and I2, the deflection angle θ2 is expressed by the following formula.

2係二次射束107之能量。 Here, a and b are constants determined by the shape or composition of the deflector 110, etc.,

2 is the energy of the secondary beam 107.

In addition, the energy dispersion Disp2 of the secondary beam 107 generated by the deflector 110 is expressed by the following formula.

Here, c and d are constants determined by the shape or composition such as the size of the deflector 110. In order to cancel the energy dispersion Disp1 of the secondary beam 107 generated by the beam splitter 105 by the deflector 110, the following equation should be satisfied.

Disp1+Disp2=0...(Equation 6)

2而算出。偏向器110之電場E2及磁場B2可使用算出之電壓V2及電流I2予以調整。藉由使用算出之電壓V2及電流I2，可簡化偏向器110之電場E2及磁場B2之調整。 Therefore, when the values of the deflection angle θ2 and the energy dispersion Disp1 are given, the voltage V2 and the current I2 supplied to the deflector 110 can be calculated based on (Equation 4) to (Equation 6). That is, the voltage V2 and the current I2 are based on the deflection angle θ2 formed by the deflector 110, the energy dispersion Disp1 generated by the beam splitter 105, and the energy of the secondary beam 107

2 and calculated. The electric field E2 and the magnetic field B2 of the deflector 110 can be adjusted using the calculated voltage V2 and current I2. By using the calculated voltage V2 and current I2, the adjustment of the electric field E2 and the magnetic field B2 of the deflector 110 can be simplified.

Using FIG. 11, a modification example of the scanning electron microscope of this embodiment will be described. In FIG. 1, a scanning electron microscope in which ExB is used as the beam splitter 105 and the primary beam 104 is moved straight to irradiate the sample 106 has been described. FIG. 11 shows a scanning electron microscope that uses an electric field sector or a magnetic field sector as the beam splitter 105 to deflect the primary beam 104 and irradiate the sample 106. That is, compared with FIG. 1, only the beam splitter 105 is different, and other configurations are the same, and the deflector 110 deflects the secondary beam 107 in a direction opposite to the beam splitter 105.

According to the scanning electron microscope of this embodiment described above, the beam can be reduced The position of the secondary beam 107 generated in the splitter 105 is shifted. By reducing the positional deviation between the secondary beams 107, the secondary beams 107 are incident on the detection parts of the detector 108, so the detection of the secondary beams 107 will not be hindered. In addition, the distortion of the beam shape of the secondary beam 107 is also improved, thereby improving the detection and resolution power.

Example 2

In the first embodiment, the case where the inclination angle θ of the detector 108 with respect to the beam splitter 105 is an arbitrary angle has been described. In this embodiment, a case where the beam splitter 105 and the detector 108 are parallel will be described. In addition, the same symbols are attached to the components having the same functions as those of the first embodiment, and the description is omitted.

Using FIG. 12, the overall structure of the scanning electron microscope of this embodiment will be described. In this embodiment, the beam splitter 105 and the detector 108 are arranged in parallel. That is, the inclination angle θ of the detector 108 with respect to the beam splitter 105 is 0, and the detector 108 is arranged perpendicular to the direction of gravity. In FIG. 12, the deflector 110 is used to deflect the secondary beam 107 in the direction opposite to the beam splitter 105, thereby correcting the positional deviation between the secondary beams 107 generated in the beam splitter 105. Furthermore, if θ=0 is substituted into (Equation 1), θ2=−θ1, so it is preferable to make the deflection angle θ1 of the beam splitter 105 and the deflection angle θ2 of the deflector 110 equal in absolute value.

According to the scanning electron microscope of the present embodiment described above, the positional deviation between the secondary beams 107 generated in the beam splitter 105 can be reduced as in the first embodiment. In addition, the distortion of the beam shape of the secondary beam 107 is also improved, thereby improving the detection resolution. Furthermore, since the detector 108 is arranged perpendicular to the direction of gravity, even when the detector 108 vibrates in the direction of gravity, the secondary beam 107 will not be positionally shifted relative to the detector 108 and can be stabilized Form an SEM image.

Example 3

In the first embodiment, the case where the secondary beam 107 is deflected in the direction opposite to the beam splitter 105 by the deflector 110 has been described. In this embodiment, a case where ExB is used as the deflector 110 and the secondary beam 107 is moved straight forward will be described. In addition, the same symbols are attached to the components having the same functions as those of the first embodiment, and the description is omitted.

Using FIG. 13, the overall structure of the scanning electron microscope of this embodiment will be described. In this embodiment, ExB is used as the deflector 110, and the secondary beam 107 travels straight in the deflector 110. That is, using the deflection angle θ2=0 formed by the deflector 110, the beam splitter 105, the deflector 110, and the detector 108 are arranged on a straight line. In Figure 13, maintain θ2=0, adjust the ratio of the electric field E2 to the magnetic field B2 in the deflector 110, thereby controlling the size of the beam shape of the secondary beam 107 in the detector 108, thereby adjusting the detection of the detector 108 Resolution. The ratio of the electric field E2 to the magnetic field B2 is adjusted according to the processing flow shown in FIG. 8.

Furthermore, when the deflection angle θ2=0, the correction of the positional deviation between the secondary beams 107 becomes slightly difficult. Therefore, in this embodiment, a deflector 110 that forms an electromagnetic field asymmetric with respect to the secondary beam 107 as shown in FIG. 14 can be used. The deflector 110 shown in FIG. 14 has a plurality of electrodes or magnetic poles 1401 to 1405 arranged along the secondary beam 107.

The side electrodes or magnetic poles 1401-1405 formed by the deflector 110 whose expansion of the electric or magnetic field is suppressed are partially turned on (ON), and the other side is all turned on. The following situation is illustrated in FIG. 14: the electrodes or magnetic poles 1403a, 1401b to 1405b are turned on, and the electrodes or magnetic poles 1401a, 1402a, 1404a, and 1405a are turned off. By operating the electrodes or magnetic poles 1401~1405 in this way, an asymmetric electromagnetic field with respect to the secondary beam 107 is formed. In Fig. 14, the range of action from the asymmetric electromagnetic field becomes longer in the secondary beam 107c. It becomes shorter in the secondary beam 107a. By adjusting the range of action from the asymmetric electromagnetic field, the position offset between the secondary beams 107 is corrected.

According to the scanning electron microscope of the present embodiment described above, the positional deviation between the secondary beams 107 generated in the beam splitter 105 can be reduced by forming an asymmetric electromagnetic field. In addition, the distortion of the beam shape of the secondary beam 107 is also improved, thereby improving the detection and resolution power. Furthermore, the secondary beam 107 travels in a straight line in the deflector 110, so the beam splitter 105, the deflector 110, and the detector 108 are arranged on a straight line, making the manufacturing of the scanning electron microscope easy.

Above, a plurality of embodiments of the charged particle beam device of the present invention have been described. The present invention is not limited to the above-mentioned embodiments, and may be embodied by changing the constituent elements within the scope not departing from the gist of the invention. In addition, a plurality of constituent elements disclosed in the above-mentioned embodiments can be appropriately combined. Furthermore, some constituent elements may be deleted from all the constituent elements shown in the above-mentioned embodiment.

101: Electron source

102: electron beam

103: Multi-beam forming part

104a: one beam

104b: one beam

104c: one beam

105: beam splitter

106: Specimen

107a: secondary beam

107b: Secondary beam

107c: secondary beam

108: Detector

110: deflector

120: Control Department

Claims (8)

A charged particle beam device, characterized by comprising: a charged particle beam source which irradiates a plurality of primary beams to a sample; and a plurality of detectors which detect each of the above-mentioned primary beams from the sample And a beam splitter that deflects the secondary beam in a direction different from the primary beam; and the charged particle beam device further includes a deflector, and the deflector is arranged at Between the beam splitter and the detector, the positional deviation between the secondary beams generated in the beam splitter is corrected; the deflector is used to change the position of the secondary beams generated in the beam splitter The deformation of the beam shape is corrected together with the position shift; the beam splitter forms a first electric field and a first magnetic field orthogonal to each other in a plane orthogonal to the primary beam, so that the primary beam advances straight And to deflect the secondary beam, the deflector forms a second electric field and a second magnetic field orthogonal to each other, and the magnitude of the second electric field and the magnitude of the second magnetic field are based on each of the primary beams being irradiated Observe the image and adjust it depending on the position. A charged particle beam device, characterized by comprising: a charged particle beam source which irradiates a plurality of primary beams to a sample; and a plurality of detectors which detect each of the above-mentioned primary beams from the sample Each secondary beam released in the middle; and A beam splitter that deflects the secondary beam in a direction different from the primary beam; and the charged particle beam device further includes a deflector disposed between the beam splitter and the detector , Correcting the position shift between the secondary beams generated in the beam splitter; the deflector shifts the deformation of the beam shape of the secondary beams generated in the beam splitter to the position And correction; the beam splitter forms a first electric field and a first magnetic field orthogonal to each other in a plane orthogonal to the primary beam, so that the primary beam advances linearly and the secondary beam is deflected toward the The deflector supplies voltage and current for forming a second electric field and a second magnetic field orthogonal to each other. The values of the voltage and the current are based on the angle at which the secondary beam is deflected by the deflector. The energy of the secondary beam generated by the splitter is dispersed and the energy of the secondary beam is set. The charged particle beam device of claim 1 or 2, wherein the detector is arranged at a position where the size of the beam shape of the secondary beam becomes less than a specific value. The charged particle beam device of claim 1 or 2, wherein the deflector deflects the secondary beam in a direction opposite to the beam splitter. The charged particle beam device of claim 1 or 2, wherein the angle at which the secondary beam is deflected by the deflector is based on the relative Set at the tilt angle of the beam splitter. The charged particle beam device of claim 5, wherein the detector is parallel to the beam splitter, and the angle θ1 at which the secondary beam is deflected by the beam splitter and the secondary beam is deflected by the deflector The angle of deflection θ2 is in the relationship of θ2=-θ1. The charged particle beam device of claim 5, wherein when the angle θ1 at which the secondary beam is deflected by the beam splitter is equal to the inclination angle θ of the detector with respect to the beam splitter, the deflector is at An electric field and a magnetic field orthogonal to each other are formed in a plane orthogonal to the secondary beam, so that the secondary beam advances straight, and the chromatic aberration of the secondary beam is corrected. The charged particle beam device of claim 7, wherein the deflector has a plurality of electrodes and a plurality of magnetic poles arranged along the secondary beam, and forms an electromagnetic field that is asymmetric with respect to the secondary beam.

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